Hello, I recently replaced the PC on the CNC Router & at the same time upgraded to Mach 4 build 4612 (from v4517) and upgraded to ESS 278.1 at the same time (from v266).  I have an MB3-ESS breakout board.  All previous parameters were copied over from my older install which was running very well.  PC was one Lenovo to another, very similar builds.
Am having issues now with all x/y/z axes all randomly skipping/clunking now and one instance of x-axis jumping off position by about 5 inches.  There are 2phase hybrid steppers on the x/y/z axis (y has master and slave), 200k pps frequency response.
- has happened now both within a gcode program and during manual jogging, slow and fast speeds, load and no-load, spindle has been both on and off during the events.
- ESS is at 40Hz default, 0.2s buffer, no backlash settings.  I have 'anti clunk' for servos 'ON', as I have a fourth axis using a servo (I don't have it installed currently, so not aware if it also has this issue, and previously I had 'anti clunk' ON with no issues).
All cables between the PC and controller are the same, no changes to to anything that would contribute noise.

Looking for any help/guidance on where I can start debugging - perhaps there is still a control parameter I missed setting correctly after the upgrades, as all hardware otherwise is the same.

(also noticed the z incremental jogging glitch, but I see that is already noted as a mach v4612 bug).
Thanks.

Update: I had neglected to install a dedicated high speed ethernet card on the new PC. I've done this now, and only a couple runs so far, but everything is fine.  I'm optimistic this was the issue as it would underpin the communication issue.
Thanks.

Update: It is still skipping.  Similar to the first time, it starts with a subtle skip and the skips get progressively worse, seems random for what axis it will happen on and time period between skipping.

At all times, I have the PC in airplane mode, no other network connections. I've double checked again all parameters, same as what I had on original setup with no issues.  Both times I also used the ESS configuration tool with no issues to set up the network and confirm communication.

Looking for any suggestions as to what to look into.
Thanks

increase the Hz to 100

Update: Thanks for the suggestion. I increased to 100Hz.  Similar to previous days, it worked fine cutting air for about 5 runs of the gcode, then same thing - a subtle skip in z-axis, followed by skip in x then large skips in y-axis.
I had the ESS advanced logging utility on - nothing apparent in the log file, it believes it is moving the position, no error registrations noted around skipping areas.  The Mach4 history tab also shows no errors.

Other specifics of this setup:
- PC is i7-7700 3.6GHz with 16GRam,
- dedicated pci express Intel Ethernet card 10/100/1000-base T connected direct to ESS with cable (same setup as before),
- PC is in airplane mode, nothing else running in background, all ESS setup suggestions were done with SCU utility when installing latest ESS plugin (power management, no updates, default IP address, firewall etc.). No apparent communication issues when installing plugin and reviewing network communications.

Thanks

I believe I've finally resolved it - a glitchy Ethernet card. Replaced that and it runs fine, back at 40Hz, no issues so far.

when you had that skipping/clunking is it also loose position ,or just have delay and then continue in very fast move to complete the movement?

Hi - it would lose position.  So when first noticing this while actually trying to make a part, it would wreck the part as it loses position during the cycle.

i think its not pc problem
because i had some issue with like this behavior,like while run( most time its some utility by M function ) its stop immediately
then jump like crazy ,but not loose position
do you use servo? steper? close loop steeper?

Hybrid steppers.

Ever since I put the new ethernet card into the CNC Router, it has worked fine.
I also put the old ethernet card into my desktop computer, and started having problems with it there as well, so I'm pretty sure now the issue was this glitchy ethernet card that would work, then stop working properly.

thanks